[Laszlo-dev] image sprites to improve app load time in DHTML

[Lorien Henry-Wilkins]

Image sprites are when you lay out all of your images on one single 
image file, and use CSS positioning to display the chunk you are after 
in your specific html <img> tag. This cuts down on the number of http 
connections you have open to your host, which should significantly 
reduce load time for pages with a large number of images (like most 
openlaszlo apps). You can read more about this here: 
http://www.websiteoptimization.com/speed/tweak/css-sprites/

It would be cool if we included a feature in the platform for automatic 
image spriting when compiling to DHTML. The platform would take all of 
your images and compose them into one Uber image, and then change all of 
your references to individual images to point to the new image file, and 
apply the necessary CSS to do positioning. I don't know if it's possible 
to do all of that with image scripting, but it would be cool if the 
developer didn't have to do it manually.

It wouldn't work for background images that are repeated in the X or Y 
directions, but it should work for other images - even ones that are 
dynamically resized.

Let me know what you think.

Lorien